Sump pump switch



Feb. 28, 1967 w. J. EKEY 3,307,000

SUMP PUMP SWITCH Filed 061;.l l5, 1965 NVENTOR. WILLIAM J. EKEY United States Patent Office 3,307,000 SUMP PUMP SWHTCH William J. Ekey, Ashland, Ghio, assigner to The F. E. i/[yers & Bro., Co., Ashland, Ohio, a corporation of hio Filed Oct. 15, 1965, Ser. No. 496,282 4 Claims. (Cl. Z130- 83) This invention relates to improvements in pressure switches and is particularly concerned with improvements in diaphragm operated pressure switches. This application is a continuation-in-part of my co-pending application Serial No. 353,791, iiled March 23, 1964, and entitled, Sump Pump Switch, now Patent No. 3,234,881.

Pressure switches are, of course, well known and diaphragm operated pressure switches are a common form which switches of this nature take. Such diaphragm operated pressure switches can be found in many locations, such as in washing machines and the like wherein liquid levels are detected thereby. Another common use of diaphragm operated pressure switches is in connection with sump pumps wherein the pressure switch is directly associated with a motor-pump assembly and is operable to detect a rising liquid level inthe region of the pump and energize the motor to pump the liquid from the said region. It is in particular connection with diaphragm operated switches of this last mentioned nature that the present application is concerned.

The diaphragm operated switches hereto-fore employed in connection with sump pumps `and the like have taken the form of a switch structure having `an loperator in the form of a spring or the like which is operatively associated with the diaphragm carried by the switch structure and which diaphragm is exposed to the liquid of which the level is to be selected. In the usual type arrangement, the diaphrgam is exposed directly to the fluid and, when it is located in a sump, the possibility and, in fact, the likelihood, exists, that the surface of the diaphragm will become soiled with foreign matter and may even acquire such a layer of sediment as to make it relatively stili". Furthermore, `substances may lbe contained in the liquid that adversely effect the diaphragm which could lead to replacement of the entire pressure switch upon failure of only the diaphragm portion there-of. This last drawback arises because the diaphragm in the usual type pressure switch is an integral part thereof and is not removable or replaceable.

With the foregoing in mind it is proposed by the present invention to construct a pressure operated switch in such a manner that the switch structure proper with its integral diaphragm will never be exposed to the soiling or corrosive inuence of liquids the level of which is operable for `actuating the switch.

It is a particular object lof the present invention to provide .a diaphragm operated pressure switch in which the diaphragm por-tion that is exposed to liquid can easily be removed and replaced.

A still further object of this invention is the provision of a pressure operated switch having an actuating diaphragm in which the actuating diaphragm is readily replaceable and forms a relatively inexpensive portion of the entire switch structure.

Still another object is the provision of the combination of a switch housing `and a diaphragm operated pressure switch therein in which the diaphragm is operable for 3,307,000 Patented Feb. 28, 1967 clamping the switch into the housing while simultaneously sealing the housing and still providing actuating means for the switch.

The several objects referred to above as well as still other objects and advantages of the present invention will become more apparent upon reference to the following speciiication taken in connection with the accompanying drawings in which:

FlGURE 1 is a fragmentary sectional View showing a portion of a motor-pump combination and also showing the switch structure acc-Ording to the present invention connected thereto;

FIGURE 2 is a perspective view showing one form which the diaphragm operator according to the present invention can take;

FIGURE 3 is another sectional perspective View showing another form which the diaphragm can take; and

FIGURE 4 is a fragmentary sectional view showing the diaphragm of FIGURE 3 housing.

Referring to the drawings somewhat more in detail, 10 indicates a sump pump structure forming no part in itself of the present invention. The details of the pump structure are fully illustrated in the co-pending application, Serial No, 353,791, now Patent No. 3,234,881, of which the present application is a -continuation-in-part. The pump structure is associated with the motor structure generally indicated at 12 and which is also fully disclosed in the said co-pending application.

Adjacent the motor 12 is an inverted cup-like switch housing 14 which is connected with the frame of the motor by a threaded nipple 16 Aand surrounding which nipple is a sealing sleeve 18 which sealingly engages both the motor frame and the switch housing. Wires 20 extend through nipple 16 into the motor frame and are therein connected to the windings 21 of the motor for supplying electric power thereto.

The wires lead into switch housing 14 and are there.l connected to a relay 22 and which relay is under the control of a pressure switch generally indicated at 24. The pressure switch is connected by wires 26 with the relay and the switch is operable, when closed, to eifect closing of the relay and, when opened, to permit the relay to open. Closing of the relay will connect the wires leading to the motor windings to the electric power lines contained within cable 26 which extends through an aperture in the top of switch housing 14. Cable 26 is sealed to the switch housing as by sealing means 28 and gland 30.

The particular construction of the pressure switch 24 is not illustrated because such switches `are well known commercial items. In any case, the switch contains contacts, usually normally open, and maintained open under the basis of a predetermined spring force. The contacts are adapted to close when urged toward closed position yby a spring member 32 contained within switch housing 34 and bearing in about the center of a diaphragm 36 arranged on the bottom open side of housing 34.

According to the present invention, a second diaphragm 3S is provided arranged in spaced substantially parallel relation to diaphragm 36. Diaphragm 38 has ia central post element 40 thereon bearing on the region of the center of diaphragm 36 operable when diaphragm 38 is flexed upwardly to cause upward flexing of diaphragm 36 and actuation of the pressure switch 24. It will be understood that the central region of diaphragms of this in position in the switch nature are usually stilened as by a metal plate or the like and that the provision of post 40 extending between diaphragm 36 ad 3S is an adequate manner of transmiting forces therebetween.

The housing 34 of pressure switch 24 has a radially extending portion 42 which fits in a oounterbore in the lower open end of switch housing 14. A clamping ring 44 is provided in a slightly larger countenbore in the open end of the switch housing and this serves to clamp the pressure switch 24 firmly in place.

A second ring 46 is provided which is held on the lower end of housing 14 by cap screws '48 and which serves to press clamp ring 44 into position in the switch housing. A sealing ring 50 is provided between rings 46 and 48 and the peripheral portion 52 of diaphragm 3S is also clamped between the rings. The clamping ring 44 is notched for receiving the ring 50 so that when screws 48 are drawn up, ring 44 will not only sealingly compress the periphery 52 of diaphragm 38 but will also compress sealing ring l) so as tightly to seal the rings 44 and 46 to the lower open end of switch housing 14. The switch housing 14 is thus tightly sealed at the bottom and likewise the space between -diaphragm 36 and 23 is also tightly sealed.

Returning to the electric cable 26, not only do the electric power line wires extend therethrough but there is also contained within the cable 26 a hollow flexible tube l52, nylon, for example, which opens at one end to the inside of switch housing 14 and at its other end, at 54 to the region adjacent the plug 56 on the end of the cable. This tube provides means for venting the interior of the motor housing and the Iswitch housing, both of which are otherwise tightly sealed against the ingress of liquids.

Turning to FIGURE 2, it will be seen that diaphragm 38 can take the form of a relatively thin rubber-like sheet y60 having a somewhat thickened rim part 62 that forms the peripheral portion `52 in YFIGURE l that is clamped between rings 44 and 46. Between the central region of the diaphragm and the rim portion there is a thin extremely llexible waved portion 64 where -most of the diaphragm exing takes place. The central portion of the diaphragm has on t-he top thereof a metal disc 66 which is provided with a plurality of apertures 68. When the diaphragm is formed, the plate 66 is placed in the mold and the material of the diaphragm extnldes through aperatures 68 and forms a ring 70 on top of the plate so that the plate and the diaphragm are permanently connected together and the entire central region of the diaphragm is stiiened so as to move as a unit.

The actuating member or post for the upper diaphragm may consist of metal or plastic or rubber-like Imaterial and is indicated at 72 in FIGURE 2 and will be seen to cornprise a dependant portion 74 adapted for snapping through central hole 76 in metal plate 66 so that the post will be retained in position on the diaphragm.

The extreme central portion of diaphragm 60 in FIG- URE 2 directly beneath aperture 76 on plate 66 may be thickened as at 78 and include a recess 80 for receiving the snap in plug portion 74 of post 72.

It has been found that the diaphragm can also be manuactured as illustrated in FIGURE 3 so as to eliminate a number ot parts and operations,

In FIGURE 3 the diaphragm is generally indicated at 90 and will be seen to comprise a relatively thick central region y92 and which region is also relatively stii. rThe diaphragm also comprises a peripheral portion 94 radially spaced from central region 92 and connected thereto by a thin exible part 96 which may normally lay as a wave as illustrated.

Portion 92 of the diaphragm at its central part has an upstanding post portion y98 which forms the portion of the diaphragm which will engage the switch diaphragm 36 and actuate the same. lIt will be apparent that the provision of the post 98 integral with the diaphragm 92 eliminates the need for an extra post between the diap'hragms. Preferably, for producing better moldings, post 9S is recessed at 100 and 102 to provide for a uniform section of the material in the central portion of the diaphragm without detracting from the stiffness of the post.

As to the peripheral portion 94, this is formed so as to have a thickened region 104 of which the radially inner and highest part 106 is so arranged that it will bear on t-he periphery of housing 3'4 of pressure switch 24. The lower radially outer por-tion 10S of rim portion 94 of the diaphragm is adapted for fitting within the counterbore in which clamp ring 44 is seated. The portion 94 furthermore com-prises the thin radially outwardly extending llange 110 which is adapted for being clamped between the outer ring on the lower end of the switch hous ing and the switch housing itself, thus sealing the interior of the switch housing from the ingress of moisture.

The one piece diaphragm construction of FIGURE 3 is more inexpensive to construct than the diaphragm illustrated in FIGURE 2 and eliminates certain operations during manufacture and assembly of the switch unit in the housing.

The need for a gasket between clamp ring 44 of the switch housing is eliminated but the switch housing is nevertheless firmly clamped into position by the diaphragm structure of 'FIGURE 3.

The diaphragm of FIGURE 3 is shown in assembly with the other parts of the switch structure in FIGURE 4 wherein it will be seen that a number of parts are eliminated from the FIGURE l arrangement and that extremely good sealing of the assembly is had. yIt will be noted in FIGURE 4 that the relatively thick ring 46 of the FIGURE l structure is replaced by relatively thin stamped plate 46a which permits the use of shorter clamp screws than are employed for ring 46.

It will be understood that this invention is susceptible to modication in order to adapt it to dilferent usages and conditions; and accordingly, it is desired to comprehend such modifications within this invention as may fall within the scope of the appended claims.

I claim:

1. lIn combination; a switch housing in the form of an inverted cup-shaped member, a pressure switch mounted in 4the lower open end of said member and having a diaphragm on the bottom of which at least the center is exposed, a second diaphragm in spaced parallel relation to the switch diaphragm and therebeneath in the said lower open end of the housing, a shoulder in the housing engaging the upper side of said switch, said second diaphragm having a thin annular peripheral portion engaging the end of said housing, a clamp ring sealingly clamping said portion to the said end of said housing, a thickened annular region on said second diaphragm immediately inside said housing extending telescopically into said housing toward said switch and engaging the lower side of said switch to hold the switch against said shoulder, a thin flexible annular region in said second diaphragm immediately inside said thickened annular region, said second diaphragm inwardly of said exible region being relatively still, and a post on top of said second diaphragm in the center thereof integral therewith and extending upwardly therefrom into engagement with the center of the switch diaphragm.

2. The combination according to claim 1 in which said housing has a second shoulder therein near the lower side of said switch, and said thickened annular region of said second diaphragm also engaging said second shoulder.

Y3. The combination according to claim 2 in which said thickened annular region of said second diaphragm comprises a raised annular portion on the upper end thereof at the radially inner side which engages the lower side of said switch.

5 6 4. The combination according to claim 1 in which said 2,777,028 1/1957 Kendall et al. 20G-83.2 ring extends radially inwardly from the peripheral portion 2,804,516 8/ 1957 Staak 10S-25 of said second diaphragm so as to overlie said thickened 2,910,003 10/ 1959 Kaatz 10S- 25 annular region thereof to provide means for clamping 3,067,302 12/ 1962 Nilsen 10S-25 said thickened annular region against the lower side of 5 3,198,122 8/ 1965 Lippke et al. 103-25 said switch.

FOREIGN PATENTS References Cited by the Examiner 548,569 11/1957 Canada- UNITED STATES PATENTS 2,635,546 4/1953 Enyeart et al. 10(3 25 10 DONLEY J. STOCKING, Prlmary Exammer.

2,686,093 4/ 1953 Clark et al. 200-83 SAMUEL LEVINE, MARK NEWMAN, Examiners. 2,687,693 8/19'54 Hudson 103-25 

1. IN COMBINATION; A SWITCH HOUSING IN THE FORM OF AN INVERTED CUP-SHAPED MEMBER, A PRESSURE SWITCH MOUNTED IN THE LOWER OPEN END OF SAID MEMBER AND HAVING A DIAPHRAGM ON THE BOTTOM OF WHICH AT LEAST THE CENTER IS EXPOSED, A SECOND DIAPHRAGM IN SPACED PARALLEL RELATION TO THE SWITCH DIAPHRAGM AND THEREBENEATH IN THE SAID LOWER OPEN END OF THE HOUSING, A SHOULDER IN THE HOUSING ENGAGING THE UPPER SIDE OF SAID SWITCH, SAID SECOND DIAPHRAGM HAVING A THIN ANNULAR PERIPHERAL PORTION ENGAGING THE END OF SAID HOUSING, A CLAMP RING SEALINGLY CLAMPING SAID PORTION TO THE SAID END OF SAID HOUSING, A THICKENED ANNULAR REGION ON SAID SECOND DIAPHRAGM IMMEDIATELY INSIDE SAID HOUSING EXTENDING TELESCOPICALLY INTO SAID HOUSING TOWARD SAID SWITCH AND ENGAGING THE LOWER SIDE OF SAID SWITCH TO HOLD THE SWITCH AGAINST SAID SHOULDER, A THIN FLEXIBLE ANNULAR REGION IN SAID SECOND DIAPHRAGM IMMEDIATELY INSIDE SAID THICKENED ANNULAR REGION, SAID SECOND DIAPHRAGM INWARDLY OF SAID FLEXIBLE REGION BEING RELATIVELY STIFF, AND A POST ON TOP OF SAID SECOND DIAPHRAGM IN THE CENTER THEREOF INTEGRAL THEREWITH AND EXTENDING UPWARDLY THEREFROM INTO ENGAGEMENT WITH THE CENTER OF THE SWITCH DIAPHRAGM. 